Snarfer is a new feed reader just released, by Snarfware. Supports both Atom, and RSS, and sports a plugin architecture to allow new feed formats to be easily incorporated. It’s free, because (like Google) it includes contextually relevant adware links above each post. The adware is unobtrusive, and unlikely to ever bother you.
It has a nice clean UI. Very spartan features, however. I would like, at minimum, to be able to post from the RSS feed to my blog. But if you don’t have a blog, it may be just the ticket for you.
Take it for a spin.